Nigeria is blessed with large deposit of Zinc ore which occur mostly in association with Lead. Zinc is the 4th most widely used metal after iron, aluminum, and copper. It is a chemical element with symbol Zn and atomic number 30; it has a melting point of 419.5 °C and the boiling point of 907 °C. In some respects zinc is chemically similar to magnesium: both elements exhibit only one normal oxidation state (+2), and the Zn2+ and Mg2+ions are of similar size. Zinc is the 24th most abundant element in Earth’s crust and has five stable isotopes. The most common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. Zinc is refined by froth flotation of the ore, roasting, and final extraction using electricity electro winning
Zinc is an essential mineral to humans, it is essential in prenatal and postnatal development. It is estimated that Zinc deficiency affects about two billion people in the developing world and is associated with many diseases. In children, deficiency causes growth retardation, delayed sexual maturation, infection susceptibility, and diarrhea. Consumption of excess zinc can cause ataxia, lethargy and copper deficiency
MINING AND PROCESSING
Zinc is the fourth most common metal in use, trailing only iron, aluminium, and copper with an annual production of about 13 million tonnes. The world’s largest zinc producer is Nyrstar. About 70% of the world’s zinc originates from mining, while the remaining 30% comes from recycling secondary zinc. Commercially pure zinc is known as Special High Grade, often abbreviated SHG, and is 99.995% pure.
Worldwide, 95% of new zinc is mined from sulfidic ore deposits, in which sphalerite (ZnS) is nearly always mixed with the sulfides of copper, lead and iron.
Zinc metal is produced using extractive metallurgy. The ore is finely ground, then put through froth flotation to separate minerals from gangue (on the property of hydrophobicity), to get a zinc sulfide ore concentrate consisting of about 50% zinc, 32% sulfur, 13% iron, and 5% SiO. Roasting converts the zinc sulfide concentrate to zinc oxide.The sulfur dioxide is used for the production of sulfuric acid, which is necessary for the leaching process.
Further processing uses either: pyrometallurgy or electro winning. Pyrometallurgy reduces zinc oxide with carbon or carbon monoxide at 950 °C (1,740 °F) into the metal, which is distilled as zinc vapor to separate it from other metals, which are not volatile at those temperatures. The zinc vapor is collected in a condenser.
In electro winning, zinc is leached from the ore concentrate by sulfuric acid.
Finally, the zinc is reduced by electrolysis. The sulfuric acid is regenerated and recycled to the leaching step.When galvanized feedstock is fed to an electric arc furnace, the zinc is recovered from the dust by a number of processes, predominately the Waelz process (90% as of 2014).
APPLICATION
Major applications of zinc include
Galvanizing (55%)
Brass and bronze (16%)
Other alloys (21%)
Miscellaneous (8%)
Zinc is most commonly used as an anti-corrosion agent and galvanizing (coating of iron and steel). Zinc is used as an anode material for batteries. It is used for anodes in lithium batteries. Powdered zinc is used in this way in alkaline batteries and the case (which also serves as the anode) of zinc–carbon batteries. Zinc is used as the anode or fuel of the zinc-air battery/fuel cell. The zinc-cerium redox flow battery also relies on a zinc-based negative half-cell
ALLOYS
A widely used zinc alloy is brass, in which copper is alloyed with anywhere from 3% to 45% zinc, depending upon the type of brass. Brass is generally more ductile and stronger than copper, and has superior corrosion resistance. These properties make it useful in communication equipment, hardware, musical instruments, and water valves.
Other widely used zinc alloys include nickel silver, typewriter metal, soft and aluminum solder, and commercial bronze.[12] Zinc is also used in contemporary pipe organs as a substitute for the traditional lead/tin alloy in pipes. Alloys of 85–88% zinc, 4–10% copper, and 2–8% aluminum find limited use in certain types of machine bearings. Alloys of zinc with small amounts of copper, aluminum and magnesium are useful in die casting as well as spin casting, especially in the automotive, electrical, and hardware industries. These alloys are marketed under the name Zamak. An example of this is zinc aluminum.
The low melting point together with the low viscosity of the alloy makes possible the production of small and intricate shapes. The low working temperature leads to rapid cooling of the cast products and fast production for assembly. Another alloy, marketed under the brand name Prestal, contains 78% zinc and 22% aluminum, and is reported to be nearly as strong as steel but as malleable as plastic. This super-plasticity of the alloy allows it to be molded using die casts made of ceramics and cement. Similar alloys with the addition of a small amount of lead can be cold-rolled into sheets. An alloy of 96% zinc and 4% aluminum is used to make stamping dies for low production run applications for which ferrous metal dies would be too expensive. For building facades, roofing, and other applications for sheet metal formed by deep drawing, roll forming, or bending, zinc alloys with titanium and copper are used.
As a dense, inexpensive, easily worked material, zinc is used as a lead replacement. In the wake of lead concerns, zinc appears in weights for various applications ranging from fishing to tire balances and flywheels.
Other industrial uses
Zinc oxide is widely used as a white pigment in paints and as a catalyst in the manufacture of rubber to disburse heat. Zinc oxide is used to protect rubber polymers and plastics from ultraviolet radiation UV
Zinc chloride is often added to lumber as a fire retardant and sometimes as a wood preservative. It is used in the manufacture of other chemicals. Zinc methyl (Zn(CH3) is used in a number of organic syntheses. Zinc sulfide (ZnS) is used in luminescent pigments such as on the hands of clocks, X-ray and television screens, and luminous paints. Crystals of ZnS are used in lasers that operate in the mid-infrared part of the spectrum. Zinc sulfate is a chemical in dyes and pigments. Zinc pyrithione is used in antifouling paints.
Zinc powder is sometimes used as a propellant in model rockets. When a compressed mixture of 70% zinc and 30% sulfur powder is ignited there is a violent chemical reaction. This produces zinc sulfide, together with large amounts of hot gas, heat, and light. Zn is used as a tracer to study how alloys that contain zinc wear out, or the path and the role of zinc in organisms.
Zinc dithiol-carbamate complexes are used as agricultural fungicides; these include Zineb, Metiram, Propineb and Ziram. Zinc naphthenate is used as wood preservative. Zinc in the form of ZDDP, is used as an anti-wear additive for metal parts in engine oil
Other uses
Dietary supplement
Treatment for common cold
MARKET
Export of crude Zinc ore is good business but refining to obtain pure Zinc ready to be used is better although it requires enormous investment so also is the return on investment. World consumption of refined lead was 15 million metric tons in 2017. The leading refined Zinc consuming countries were China, the United States, and Germany. Demand for Zinc worldwide is expected to grow largely because of increased consumption in China, which is being driven by growth in the automobile and other related products
REQUIREMENT AND CONDITIONS FOR MINING LEAD IN NIGERIA
There are two options available to a company or an individual to enter into the mining industry in Nigeria.
Through the acquisition of an existing mining Lease from the original owner, approval must be obtained from the Ministry of Solid Minerals Development for such a purchase.
Fresh mining lease
Procedure for Mineral Title Licences/Leases and Permits:
- Duly completed application form
- Coordinates of the area of application
- Certificate of incorporation
- Attestation
- Letter of consent from landowner(s)/occupier(s)
- Types of minerals
- Work programme/pre-feasibility report
- Evidence of payment
- Technical capability
- Financial capability
In order to encourage investment in the solid minerals industry in Nigeria, Government is offering the following incentives
- 3-5 years Tax Holiday
- Deferred royalty payments
- Possible capitalization of expenditure on exploration and surveys
- Extension of infrastructure such as roads and electricity to mining sites, and provision of 100% foreign ownership of mining concerns.
The mining industry in Nigeria is regulated by the Nigerian Minerals and Mining Act of 2007, National Minerals and Metals Policy 2008 and Nigerian Minerals and Mining Regulations 2011.
CONCLUSION
Business Advisory Network ‘BAN’ will work with you and assist you to process mining lease from the federal government. We will help you source for a site with rich mineral content. Mining is a technical field although the financial reward is enormous; therefore to succeed you need experts to guide you to avoid fatal mistakes that will erode your capital.
Other things BAN can do for you include but not limited to help you to determine the grade of Zinc ore in the site, source market for your mined minerals, both locally and internationally BAN will also help you arrange security at your mining sites. It will interest you to know that export of refined pure ZINC is where you make a kill. BAN will help you to set up a refinery for Zinc ore in Nigeria. The capital outlay for this is huge but even so much more is the return on investment.